The aim of this project was to understand the fundamental aerodynamics' principles within an engineering approach. Wind forces acting over bodies are usually defined in terms of the aerodynamic - lift and drag - coeffcients, which can be easily measured in a wind tunnel. Aerodynamic coeffcients measured in models are representative as long as they are obtained in the same ow regime than the body under study. Flow regimes are characterized by the Reynolds' number, Rea. Most of the bodies of engineering interest move in a turbulent regime at a very high Re. Thus, wind tunnel measurements must ensure a high enough Re value to be representative. We determined the coeffcients by different experimental methods, in order to compare them and reveal their limitations. Finally, the aerodynamic effciency of the different studied bodies is compared. 2015/2016